KR20200019950A - Robot Arm Wrist & Dual Arm Robot - Google Patents

Abstract

The wrist of the robot arm includes a proximal end connector, a first wrist link that rotates about a first wrist axis, a second wrist link that rotates about a second wrist axis, and a third wrist axis that rotates about an end. A wrist drive device including a front end side connector connected to the effector, a drive source, and an interlocking device. The interlock device rotates the second wrist link by -2α ° and also rotates the front-side connector by α ° when the first wrist link rotates by any α ° from the state where the first wrist axis and the third wrist axis overlap. . An axis extending direction of each of the first wrist axis, the second wrist axis, and the third wrist axis is parallel to a predetermined plane, and the distance from the first wrist axis to the second wrist axis and from the second wrist axis to the third wrist axis. The distance is the same

Description

Robot Arm Wrist & Dual Arm Robot

The present invention relates to the structure of a wrist connecting the robot arm and the end effector and the structure of a dual arm robot having such a wrist.

Conventionally, a dual arm robot with two horizontal articulated robot arms is known. Patent document 1 is disclosing such a dual arm robot.

The dual arm robot of patent document 1 is equipped with two horizontal articulated robot arms of an upper arm and a lower arm. The rotation axis of the base end of the upper arm and the rotation axis of the base end of the lower arm are arranged side by side up and down. In such a dual arm robot, a working shaft is provided at the tip of each arm, and the working shaft can be moved up and down with respect to the arm by a ball screw mechanism.

In general, the robot is equipped with an end effector through the wrist at the tip of the robot arm, and works with the end effector. A robot having a lifting shaft at the proximal end of the arm for vertical movement of the end effector and lifting and moving the arm and the end effector integrally on the lifting shaft, or a lifting shaft at the distal end of the arm and having an end effector with respect to the arm at the lifting shaft. A robot for lifting and moving is known. In the robot in which the base ends of the two arms are arranged side by side in the vertical direction as in Patent Document 1, the latter is adopted because it is difficult to move the base ends of the arms up and down.

As a lifting shaft provided in the tip end of an arm, the ball screw mechanism disclosed by patent document 1, the linear motion mechanism comprised by the rail and the slide, etc. are known, for example. On the other hand, in patent document 2 and patent document 3, the link type wrist which has the function which raises and lowers an end effector to the tip part of an arm is proposed.

The wrist (wrist device) of patent document 2 has the 1st wrist link (1st wrist arm) which rotates about the 1st rotational axis located in the front-end | tip part of arm, and the 2nd rotational shaft located in the front-end | tip part of this 1st wrist linkage. A second wrist link (second wrist arm) rotating around the center is provided, and a holding portion of an end effector (hand) is provided on the second wrist link. In such a wrist mechanism, the end effector has a relationship between the first wrist link and the second wrist link such that the action point moves on the same straight line while changing posture.

The transfer robot of Patent Literature 3 includes an arm, a rotating body rotatably supported at the distal end of the arm, a four-section link mechanism consisting of first to third links, a rotating member rotatably supported on the third link, and a rotating member. It has a connected end effector. This transfer robot has a link ratio of a four-section link mechanism that allows the end point of action to move while maintaining its posture on the same straight line.

Japanese Patent Laid-Open No. 7-276271 Japanese Utility Model Publication Japanese Patent Laid-Open No. 5-301181

According to the robot provided with the lifting shaft which raises and lowers an end effector with respect to an arm like patent document 1, the vertical dimension of the lifting mechanism containing the lifting shaft provided in the front-end | tip of an arm becomes larger than the lifting width of the end effector with respect to an arm. Such a robot is not suitable for inserting, for example, an arm tip including an end effector and a lifting device into a space having a narrow top and bottom width.

Therefore, it is considered to install a wrist on the robot, which includes a plurality of links connected as in Patent Document 2 and Patent Document 3, and has a function of raising and lowering the end effector with respect to the tip of the arm. However, in the technique of Patent Literature 2, when the end effector is lifted with respect to the tip of the arm, the posture of the end effector changes. In addition, in the technique of Patent Literature 3, the end effector can be raised and lowered with respect to the tip of the arm while maintaining the posture of the end effector. However, it is difficult to suppress the vertical dimension of the wrist in order to form a four-section link.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and an object thereof is to compare the end effector with respect to the arm while suppressing the dimension in a direction orthogonal to a predetermined plane in which the tip of the arm moves, compared with a conventional robot having a lifting shaft at the tip of the arm. It is to provide a robot capable of extending the movement range in a direction orthogonal to a predetermined plane.

The wrist of the robot arm according to an embodiment of the present invention is a wrist connecting the robot arm and the end effector whose tip is moved in a predetermined plane, a proximal side connecting body connected to the robot arm, and the proximal side connecting body A first wrist link connected to the proximal end connecting body so as to be rotatable about a first wrist axis defined in the first wrist link, and a first wrist link connected to the first wrist link so as to be rotatable about a second wrist axis defined in the first wrist link. A second wrist link that is connected to the second wrist link so as to be rotatable about a third wrist axis defined in the second wrist link and is connected to the end effector, and the first wrist link And a drive source for supplying rotational power to the wrist, and a linkage device for interlocking the second wrist link and the tip side connection body to the rotation of the first wrist link. And the axis extending directions of the first wrist axis, the second wrist axis, and the third wrist axis are parallel to the predetermined plane, and the distance from the first wrist axis to the second wrist axis and the second wrist axis. The distance from the wrist axis to the third wrist axis is the same, and the first wrist link is arbitrarily centered on the first wrist axis from the state in which the interlock device overlaps the first wrist axis and the third wrist axis. When rotating α °, the second wrist link is rotated by −2α ° about the second wrist axis and the tip side connector is rotated α ° about the third wrist axis. Here, in the above, the end effector may be directly connected to the distal end connector, or may be connected to the distal end connector via an axis or a link.

In addition, the dual-arm robot according to an embodiment of the present invention, a pair of robot arm whose tip is moved in a predetermined plane, the end effector installed on each of the robot arm, the robot arm and the end effector are connected And a controller for controlling the operation of the wrist, the robot arm, the end effector, and the wrist.

In the wrist of the robot arm of the above-mentioned structure and the dual arm robot provided with such a wrist, the position of the end effector of the direction orthogonal to the predetermined plane to which the front-end | tip part of the robot arm of a 3rd wrist axis moves (henceforth "Z direction") is an end effector. Is moved in the same manner as the position in the Z direction of the front end side connecting body. The third wrist axis moves on a straight line passing through the first wrist axis and extending in the Z direction. The maximum movement range of the third wrist axis in the Z direction is four times the distance from the first wrist axis to the second wrist axis. In addition, the width (dimensions in the direction orthogonal to the link length) of the first wrist link and the second wrist link can be easily reduced by design rather than the dimension in the direction parallel to the axis center of the lifting shaft provided in the distal end of the conventional robot arm. have.

Therefore, in the wrist of the robot arm of the above configuration and the dual arm robot having such a wrist, the Z-direction of the end effector relative to the arm is suppressed while suppressing the dimension in the Z direction compared with a conventional robot having a lifting shaft at the tip of the robot arm. Extending the moving range can be easily realized.

According to the present invention, compared to a conventional robot having a lifting shaft at the tip of the arm, the direction perpendicular to the predetermined plane of the end effector for the arm is suppressed while suppressing the dimension of the direction orthogonal to the predetermined plane at which the tip of the arm moves. A robot can be provided that can extend the range of movement.

1 is a schematic front view of a dual arm robot according to an embodiment of the present invention.
FIG. 2 is a schematic plan view of the dual arm robot shown in FIG. 1.
3 is a front view showing a schematic configuration of the wrist.
4 is a schematic view of section IV-IV of FIG. 3.
5 is a schematic view of the VV cross section of FIG. 3.
It is a figure which shows the installation form of a flexible hose.
It is a figure which shows the installation form of a flexible hose.
7 is a view for explaining the operation of the wrist.
FIG. 8 is a diagram showing the movement range in the Z direction of the end effector with respect to the arm by the wrist. FIG.
It is a figure which shows the modification of the wrist of the dual arm robot.
It is a figure which shows the modification of the wrist of the dual arm robot.
It is a figure which shows the modification of the wrist of the dual arm robot.
It is a figure which shows the structure of the control system of a dual arm robot.
13 is a view for explaining the advantages of the wrist according to the embodiment of the wrist including a rail-type linear motion device.
14 is a view for explaining the advantages of the wrist according to the embodiment of the wrist including a rail type linear device.
15 is a front view illustrating a schematic configuration of a wrist according to a modification.
16 is a schematic view of the XVI-XVI cross section of FIG. 15.

Next, an embodiment of the present invention will be described with reference to the drawings.

[Schematic Configuration of Dual Arm Robot]

1 is a schematic front view of the dual arm robot 1, and FIG. 2 is a schematic plan view of the dual arm robot 1. 1 and 2, a dual arm robot 1 according to an embodiment of the present invention includes a base 2 and two robot arms supported by the base 2 (hereinafter, referred to as “arm 3”). ), The end effector 5 connected to the distal end of each arm 3, the wrist 4 provided between the arm 3 and the end effector 5, and the dual arm robot 1 A controller 6 for controlling the operation.

[Structure of Arm 3]

The arm 3 is an articulated robotic arm configured to move the tip portion within a predetermined plane. Such robotic arms include, for example, horizontal articulated robotic arms. Below, the direction orthogonal to the plane which the front-end | tip part of the arm 3 moves is demonstrated by "Z direction". The two arms 3 have substantially the same structure, and the structure of one arm 3 is demonstrated below, and the description of the structure of the other arm 3 is abbreviate | omitted.

The arm 3 has a first link 31 and a second link 32 connected in sequence from the proximal end side.

The proximal end of the first link 31 is rotatably supported on the base shaft 21 which is mounted on the base 2. At the center of the axis of the base shaft 21, a first axis A1 extending in the Z direction is defined. In the 1st link 31, the 1st rotation drive device 61 which rotates the 1st link 31 with respect to the base shaft 21 is provided. The 1st rotation drive device 61 is comprised by the gear mechanism etc. which contain a motor and a reducer, for example (all are not shown).

A second axis A2 extending in the Z direction is defined at the tip end of the first link 31. The distal end of the second link 32 is connected to the distal end of the first link 31 so as to be rotatable about the second axis A2. In the arm 3 of one of the two arms 3, the second link 32 is connected to the lower side of the first link 31 in the ground of FIG. 1, and in the other arm 3. The second link 32 is connected above the first link 31 in the ground of FIG. 1.

In the 1st link 31, the 2nd rotation drive apparatus 62 which rotates the 2nd link 32 with respect to the 1st link 31 is provided. The 2nd rotation drive device 62 is comprised by the gear mechanism etc. which contain a motor and a reducer, for example (all are abbreviate | omitted). A wrist connecting portion 33 to which the wrist 4 is connected is installed at the distal end of the second link 32.

The proximal ends of the first links 31 of the two arms 3 are arranged side by side in the Z direction, and the first links 31 of the two arms 3 rotate about the first axis A1. Then, in one arm 3, the second link 32 is the Z of the first link 31 so as to offset the difference in the position in the Z direction of the base end portions of the first links 31 of the two arms 3. It is arrange | positioned in one direction, and in the other arm 3, the 2nd link 32 is arrange | positioned on the opposite side to the Z direction of the 1st link 31. As shown in FIG. Accordingly, the position in the Z direction of the wrist connecting portion 33 provided at the distal end of the second link 32 of the two arms 3 is substantially the same, and the distal ends of the two arms 3 are substantially the same. Move in the plane.

[Structure of Wrist 4]

The wrist 4 has a function of connecting the arm 3 and the end effector 5 while simultaneously moving the end effector 5 in the Z direction with respect to the arm 3.

FIG. 3 is a front view showing a schematic configuration of the wrist 4 according to the first embodiment, FIG. 4 is a schematic view of the IV-IV cross section of FIG. 3, and FIG. 5 is a schematic view of the V-V cross section of FIG. 3. As shown in FIGS. 1-3, the wrist 4 includes a proximal end connector 40 connected to the distal end of the arm 3, a first wrist link 41, and a second wrist link 42. And a front end side connecting body 43 and a wrist driving device 44. The wrist 4 according to the present embodiment is further provided with a motor 48 which is held by the front end side connecting member 43 and constitutes the fourth wrist axis L4. A fourth wrist axis L4 is defined at the center of the output shaft of the motor 48. The output from the output shaft of the motor 48 is transmitted to the interface 48a to which the end effector 5 is connected via a gear mechanism (not shown) including a speed reducer. However, the end effector 5 may be directly connected to the front end side connecting body 43.

The first wrist link 41 is connected to the proximal end connector 40 so as to be rotatable about the first wrist axis L1 defined in the proximal end connector 40. The second wrist link 42 is connected to the first wrist link 41 so as to be rotatable about the second wrist axis L2 defined in the first wrist link 41. The front end side connecting member 43 is connected with the second wrist link 42 so as to be rotatable about the third wrist axis L3 defined in the second wrist link 42. The first link length, which is the distance between the first wrist axis L1 and the second wrist axis L2, and the second link length, which is the distance between the second wrist axis L2 and the third wrist axis L3, is substantially Same as A bracket 49 is coupled to the front end side connecting member 43, and the bracket 49 has a motor holding unit 49a for holding the motor 48 and an end portion of the flexible hose 50 to be described later. Hose support 49b is provided.

The extending directions of the respective axes of the first wrist axis L1, the second wrist axis L2, and the third wrist axis L3 are parallel to the plane in which the distal end of the arm 3 moves, that is, in the Z direction. Orthogonal. The extension direction of the fourth wrist axis L4 is parallel to the Z direction.

The wrist drive device 44 is composed of a linkage device 46 for interlocking the second wrist link 42 and the tip side connecting body 43 with the rotation of the first wrist link 41. According to the present embodiment, the interlock device 46 is composed of casings 58 and 74 forming the outline of each wrist link 41 and 42 and a gear train formed therein. Hereinafter, the interlocking device 46 will be described in detail.

The proximal end connector 40 has a casing 51 fixed to the wrist connection 33 of the second link 32. As shown in detail in FIG. 5, the casing 51 is provided with a motor 45. In addition, a first rotating shaft 52 around the first wrist axis L1 is fixed to the casing 51. The motor 45 is located below the second link 32 when the second link 32 is connected to the lower portion of the first link 31, and the second link 32 is the first link 31. If connected to the upper portion of the) is located above the second link. Accordingly, the straight line connecting the first rotation shaft 52 and the output shaft of the motor 45 is inclined upward or downward from the horizontal.

The output from the output shaft of the motor 45 is transmitted to the drive gear 55 provided in the casing 51 via a gear mechanism (not shown) including a speed reducer. The rotational power of the drive gear 55 is transmitted to the input gear 90 through the intermediate gear 89 which meshes with the drive gear 55 and the input gear 90.

As shown in FIG. 4, the boss of the input gear 90 is rotatably supported by the casing 51. A casing 58 of the first wrist link 41 is fixed to the boss of the input gear 90. A second rotating shaft 59 around the second wrist axis L2 is fixed to the casing 58.

In the casing 58, the first gear 91 is fixed to the first rotation shaft 52. In the casing 58, the second gear 92 is fixed to the second rotation shaft 59. In the casing 58, an intermediate gear 95 meshes with the first gear 91 and the second gear 92 and transmits rotational power therebetween.

The boss of the second gear 92 is rotatably supported by the second rotation shaft 59, and the casing 74 of the second wrist link 42 is fixed to the boss of the second gear 92. The distal end side connecting member 43 is rotatably supported about the third wrist axis L3 at the distal end of the casing 74 of the second wrist link 42.

In the casing 74, the third gear 93 is fixed to the second rotation shaft 59. In the casing 74, the fourth gear 94 is fixed to the front end side connecting body 43. In the casing 74, three intermediate gears 96a, 96b, 96c are provided which transmit rotational power from the third gear 93 to the fourth gear 94. In this manner, the wrist 4 is configured with a gear train that extends from the drive gear 55 to the fourth gear 94.

In the wiring or piping extending from the arm 3 to the motor 48 or the end effector 5, the proximal end is coupled to the distal end of the arm 3, and the distal end is coupled to the hose support 49b of the bracket 49. Passes through the flexible hose 50. For example, as shown in FIG. 6A, the flexible hose 50 is provided to have a half loop shape that is bent laterally when viewed from the front of the dual arm robot 1. The installation form of such a flexible hose 50 is advantageous in that the dimension of a height direction is suppressed. In addition, the flexible hose 50 is provided so that it may become the half loop shape bent upward, for example as shown in FIG. 6B. The installation form of such a flexible hose 50 is advantageous in that the twist of the flexible hose 50 can be suppressed.

Here, the wiring or piping extending from the arm 3 to the motor 48 or the end effector 5 may pass through the inside of the wrist 4. In FIG. 4, the root R of the piping or wiring passing through the casings 51, 58, 74 of the wrist 4 is shown by the dashed-dotted line.

According to the wrist 4 of the above-mentioned structure, when the drive gear 55 is rotationally driven by the output of the motor 45, the rotational power will be transmitted to the input gear 90, and the input gear 90 and the casing 58 will be carried out. The first wrist link 41 including a rotation about the first wrist axis (L1). When the first wrist link 41 rotates about the first wrist axis L1, the second rotation axis 59 revolves around the first wrist axis L1. The intermediate gear 95 and the second gear 92 rotate by the revolution of the second rotation shaft 59, and the second wrist link 42 including the second gear 92 and the casing 74 is second Rotate around the wrist axis (L2). Furthermore, when the second wrist link 42 rotates about the second wrist axis L2, the front end side connector 43 revolves around the second wrist axis L2. The intermediate gears 96a and 96b and the fourth gear 94 are rotated by the revolution of the front end connector 43, and the front end connector 43 including the fourth gear 94 is the third wrist shaft. Rotate around (L3).

7, the first wrist link 41 is moved from the folded state so that the third wrist axis L3 moves on a straight line in the Z direction passing through the first wrist axis L1. When 1 ° rotates about the wrist axis L1, the second wrist link 42 rotates about -2α ° about the second wrist axis L2, and the distal end link 43 is the third wrist. The gear ratio of each gear is determined so as to rotate α ° about the axis L3.

FIG. 7 is a view for explaining the operation of the wrist 4 in which the first wrist link 41 is rotated α ° about the first wrist axis L1 from the folded state. Here, in the wrist 4 in the folded state, the longitudinal direction of the first wrist link 41 and the second wrist link 42 is horizontal, and the first wrist axis L1 and the third wrist axis L3 are horizontal. Are overlapped. As shown in FIG. 7, when the first wrist link 41 is rotated α ° about the first wrist axis L1 from the folded wrist 4, the second wrist link 42 is folded. From the second wrist axis L2 around the second wrist axis L2, and the distal end side connecting member 43 rotates around the third wrist axis L3 from the folded state. Where α is any number.

According to the wrist 4 operating as described above, the third wrist axis L3 moves on a straight line parallel to the Z direction passing through the first wrist axis L1, and the fourth wrist axis L3 moves to the front end side connecting member 43. The posture of the end effector 5 connected directly or through the wrist axis L4 is kept constant regardless of the position of the third wrist axis L3 in the Z direction.

8 shows the movement range in the Z direction of the end effector 5 with respect to the arm 3, according to the wrist 4 of the above configuration. When the first link length and the second link length of the wrist 4 are set to L, the reach range of the third wrist axis L3 at the same level as the distal end connecting member 43 to which the end effector 5 is connected. 2 L from either of the first wrist axis L1 at the same level as the second link 32 of the arm 3 in one of the Z directions, and from the first wrist axis L1 to the other of the Z directions. 4L is the sum of 2L. Here, the first link length is the distance between the first wrist axis L1 and the second wrist axis L2, and the second link length is the distance between the second wrist axis L2 and the third wrist axis L3. to be.

Further, the dimension in the Z direction of the folded wrist 4 is the dimension in the link width direction of the first wrist link 41 or the second wrist link 42. Here, the link width direction is a direction orthogonal to the link length. The dimension of the link width direction of the 1st wrist link 41 or the 2nd wrist link 42 reduces the diameter of the 1st gear 91 or the 4th gear 94 in the interlocking apparatus 46 of this embodiment. It is easy to design small. In order to enlarge the movement range of the end effector 5 with respect to the arm 3 in the Z direction, and to suppress the dimension of the link width direction of the 1st wrist link 41 or the 2nd wrist link 42, a 1st wrist The link 41 or the second wrist link 42 is elongated in the link length direction.

The first wrist link 41 of the wrist 4 of the above configuration is capable of 360 ° rotation in the forward and reverse directions about the first wrist axis L1. 9 to 11 show a modification of the shape of the wrist 4 of the above configuration.

For example, as shown in FIG. 9, when the dual arm robot 1 is viewed from the front, the pair of wrists 4 are both wrists between the second wrist axis L2 of the two wrists 4. It may be in the form where the first wrist axis (L1) of (4) is located. This form is advantageous because the magnetic interference can be easily avoided even when the two end effectors 5 are approached in a scene in which the small member is moved by the dual arm or when the operation is performed by the dual arm for the small member.

Further, for example, as shown in FIG. 10, when the dual arm robot 1 is viewed from the front, a pair of wrists 4 are located between the first wrist axes L1 of both wrists 4. The second wrist axis L2 of both wrists 4 may be formed. This configuration is advantageous because the amount of protrusion to the side of the wrist 4 can be reduced in the scene in which the wide member is moved by the dual arm.

Also, for example, as shown in FIG. 11, when the dual arm robot 1 is viewed from the front, the pair of wrists 4 may have a first wrist axis L1 and a second wrist axis of both wrists 4. The straight line connecting the wrist axis (L2) may be in the form of being parallel. This form is advantageous because the work can be avoided in a scene where an interference is on one side of the dual arm robot 1 while avoiding collision with the interference.

Whether the wrist 4 of the two arms 3 of the dual arm robot 1 will use any of the illustrated forms is determined in accordance with the contents of the work performed by the dual arm robot 1, so that the dual arm robot ( 1), the controller 6 operates the wrist 4 as taught.

[Configuration of Control System of Dual Arm Robot 1]

12 is a diagram illustrating a configuration of a control system of the dual arm robot 1. As shown in FIG. 12, the operation of the first rotational drive 61, the second rotational drive 62, and the wrist drive 44 of each arm 3 and the operation of the end effector 5 are: It is controlled by the controller 6.

The controller 6 is a so-called computer, and includes, for example, a processing unit (processor) such as a microcontroller, a CPU, an MPU, a PLC, a DSP, an ASIC or an FPGA, and a storage device such as a ROM or a RAM (all illustrated). Is not). The storage device stores programs executed by the processing device, various fixed data, and the like. The storage device also stores data for controlling the operations of the arm 3 and the wrist 4, data relating to the shape, dimensions, and motion of the end effector 5.

In the controller 6, a process for controlling the operation of the arm 3, the wrist 4 and the end effector 5 is performed by the arithmetic processing unit reading and executing software such as a program stored in the storage device. Here, the controller 6 may perform each operation through centralized control by a single computer, or may perform each operation through distributed control by cooperation of a plurality of computers.

The controller 6 operates the arm 3 and the wrist 4 to move the predetermined wrist control point to an arbitrary target position. The wrist control point is defined, for example, at the tip side connector 43 or the interface 48a. The 1st rotation drive device 61 and the 2nd rotation drive device 62 are provided with the rotation position detector which detects the rotation position of the output shaft of the motor provided, and the controller 6 has the output shaft detected by this rotation position detector. The position of the predetermined arm control point with respect to the predetermined reference point of the dual arm robot 1 can be obtained based on the rotational position of. The arm control point is, for example, the intersection of the interface 48a, the joint surface of the end effector 5, and the fourth wrist axis L4.

In addition, the wrist drive device 44 is provided with a rotation position detector (not shown) for detecting the rotation position of the output shafts of the provided motors 45 and 48, and the controller 6 outputs the output shaft detected by the rotation position detector. The position and posture of the wrist control point with respect to the predetermined wrist reference point can be obtained according to the rotation direction of the. The controller 6 can calculate the position of the wrist control point with respect to the predetermined reference point of the dual arm robot 1 from the position of the obtained arm control point and the position and posture of the wrist control point.

As described above, the wrist 4 according to the present embodiment is a wrist 4 which connects the robot arm 3 and the end effector 5 whose tip portion moves in a predetermined plane, and the robot arm 3 and First wrist link 41 connected to the proximal end connector 40 to be connected to the proximal end connector 40 so as to be rotatable about the first wrist axis L1 defined in the proximal end connector 40 to be connected. ), A second wrist link 42 connected to the first wrist link 41 so as to be rotatable about the second wrist axis L2 defined in the first wrist link 41, and a second wrist link ( A first side wrist linkage 43 connected to the second wrist link 42 and connected to the end effector 5 so as to be rotatable about a third wrist axis L3 defined in 42); Drive source (motor 45) which supplies rotational power to 41, and the interlocking device 46 which connects the 2nd wrist link 42 and the front-side connector 43 to the rotation of the 1st wrist link 41, With Wrist drive device 44 is provided. Here, the end effector 5 may be directly connected to the front end side connecting body 43, or may be connected through the shaft or the link added to the front end side connecting body 43. According to this embodiment, the end effector 5 is connected to the front end side connecting body 43 via the fourth wrist axis L4 which is a rotational axis (orbiting axis) in the horizontal direction.

The extending directions of the respective axes of the first wrist axis L1, the second wrist axis L2, and the third wrist axis L3 are parallel to a predetermined plane, and the second wrist axis from the first wrist axis L1. The distance to L2 and the distance from the second wrist axis L2 to the third wrist axis L3 are the same, and the linkage device 46 further comprises a first wrist axis L1 and a third wrist axis ( When the first wrist link 41 rotates any α degrees about the first wrist axis L1 with L3) overlapping, the second wrist link 42 is centered on the second wrist axis L2. It rotates by -2 (alpha), and it is comprised so that the front end side connecting body 43 may rotate (alpha) about the 3rd wrist axis | shaft L3.

In addition, the dual arm robot 1 according to the embodiment includes a pair of robot arms 3 whose tip portions move within a predetermined plane, end effectors 5 provided for each of the robot arms 3, and a robot. The wrist 4 which connects the arm 3 and the end effector 5, and the controller 6 which controls the operation of the robot arm 3, the end effector 5, and the wrist 4 are provided.

The robot arm 3 includes a first link 31 and a second link 32 to which one proximal end of the first link 31 is connected, at the distal end of the first link 31. In addition, the wrist 4 includes a drive source of the wrist 4 and the motor 45 being installed in the proximal end connection body 40 such that the motor 45, which is the driving source, is located above and below the second link 32. The interference of one link 31 is avoided.

In the dual arm robot 1, the controller 6 is provided between the two wrists (L) between the first wrist axis L1 of the two wrists 4, for example, as shown in FIG. 10. The wrist 4 may be operated so that the second wrist axis L2 of 4) is positioned. In addition, as shown in FIG. 9, for example, the controller 6 may include a first wrist axis of both wrists 4 between the second wrist axis L2 of both wrists 4. The wrist 4 may be operated so that L1) is positioned. In addition, the controller 6 is, for example, as shown in FIG. 11, so that the straight line connecting the first wrist axis L1 and the second wrist axis L2 of both wrists 4 is parallel to each other. The wrist 4 may be operated.

In the wrist 4 and the dual arm robot 1 of the above-described configuration, the position in the direction orthogonal to the predetermined plane (that is, the Z direction) where the distal end of the robot arm 3 of the third wrist axis L3 moves is the end. It moves similarly to the position in the Z direction of the front end side connecting body 43 to which the effector 5 is connected. The third wrist axis L3 moves on a straight line passing through the first wrist axis L1 and extending in the Z direction. The maximum movement range of the third wrist axis L3 in the Z direction is 4 of the distance (that is, the first link length L) from the first wrist axis L1 to the second wrist axis L2. It is doubled. In addition, the link widths (dimensions in the direction orthogonal to the link length) of the first wrist link 41 and the second wrist link 42 are larger than those in the direction parallel to the axis center of the lifting shaft provided in the distal end of the conventional robot arm. It can be easily reduced by design.

Therefore, in the wrist 4 of the robot arm 3 of the above-mentioned structure, and the dual arm robot 1 provided with such a wrist 4, Z direction compared with the conventional robot provided with the lifting shaft in the front-end | tip of a robot arm. It is possible to easily realize the extension of the movement range in the Z direction of the end effector 5 with respect to the arm 3 while suppressing the dimensions of the.

13 and 14 illustrate the advantages of the wrist 4 according to the embodiment of the wrist 104 including the rail type linear device. In this figure, the dual arm robot 101 according to the prior art with the wrist 104 including the rail type linear device is identical to the dual arm robot 1 with the wrist 4 according to the present embodiment. It shows the work being done.

The robots 1 and 101 shown in FIG. 13 perform a job of supplying a plate-shaped work W to the press apparatus 161. Each of the robots 1 and 101 is equipped with an end effector 5 and 105, which is equipped with an adsorption hand for adsorbing and holding the plate-shaped workpiece W. In the robot 101 according to the prior art, since the rail type linear device extending in the vertical direction of the wrist 104 cannot be inserted into the press device 161, the workpiece W is predetermined within the press device 161. The travel distance required to carry in to the press position of is provided by the dimension of the end effector 105. As shown in FIG. On the other hand, in the robot 1 according to the present embodiment, not only the end effector 5 but also the arm 3 and the wrist 4 can be inserted into the press device 161, compared with the robot 101. (5) can be reduced.

In addition, the robots 1 and 101 shown in FIG. 14 perform a task of supplying a semiconductor substrate to the semiconductor exposure machine 162. The semiconductor exposure machine 162 is provided with an openable door on the stage. In the robot 101 according to the prior art, since the linear device of the wrist 104 cannot be inserted between the door and the stage, the end effector 105 provides a travel distance required to bring the semiconductor substrate to a predetermined position on the stage from below the door. We procure in dimensions of). On the other hand, in the robot 1 according to the present embodiment, since the arm 3 and the wrist 4 as well as the end effector 5 can be inserted between the door and the stage, the end effector 5 is compared with the robot 101. ) Can be reduced.

According to the example of the work shown in Figs. 13 and 14, since the robot 1 according to the present embodiment can reduce the dimensions of the end effector 5 compared with the robot 101 according to the prior art, the end effector ( The warpage and deformation of 5) can be suppressed, and stable operation can be performed.

[Modification]

While the preferred embodiments of the present invention have been described above, modifications of the details of specific structures and / or functions of the embodiments may be included in the present invention without departing from the spirit of the present invention. The structure of said wrist 4 can be changed as follows, for example.

For example, in the above embodiment, the linkage 46 of the wrist drive 44 uses a gear train, but the linkage 46 of the wrist drive 44 includes a pulley and a transmission belt. It may be an electric mechanism.

15 is a front view showing a schematic configuration of the wrist 4A according to the first modification. 16 is a schematic view of the XVI-XVI cross section of FIG. 15. Here, in the description of this modification, the same reference numerals are given to the same or similar members as in the above-described embodiment, and detailed description thereof will be omitted.

As shown in FIGS. 15 and 16, the wrist 4A according to the modification has a first proximal connector 40 connected to the distal end of the second link 32, and a first proximal connector 40. A first wrist link 41 rotatably connected about the wrist axis L1 and a second wrist rotatably connected about the second wrist axis L2 at the distal end of the first wrist link 41. A link 42 and a front end side connecting member 43 rotatably connected to a third wrist axis L3 at the distal end of the second wrist link 42. The end effector 5 is connected to the front end side connecting member 43.

The proximal end connector 40 has a casing 51 fixed to the wrist connection 33 of the second link 32. The motor 45 is attached to the casing 51. The output from the output shaft of the motor 45 is transmitted to the drive pulley 55A provided in the casing 51 via a gear mechanism (not shown) including a speed reducer.

The first rotating shaft 52 around the first wrist axis L1 is fixed to the casing 51. An input pulley 56 is relieved in the first rotation shaft 52 in the casing 51, and a boss of the input pulley 56 is supported by the casing 51 so as to be rotatable. An endless transmission belt 57 is wound around the driving pulley 55A and the input pulley 56. In the casing 51, a tension roller 81 for adjusting the tension of the transmission belt 57 is provided.

The casing 58 of the first wrist link 41 is fixed to the boss of the input pulley 56. A second rotating shaft 59 around the second wrist axis L2 is fixed to the casing 58.

In the casing 58, the first pulley 53 is fixed to the first rotation shaft 52. In the casing 58, a second pulley 72 is relieved about the second rotation shaft 59. An endless transmission belt 73 is wound around the first pulley 53 and the second pulley 72. In the casing 58, a tension roller 82 for adjusting the tension of the transmission belt 73 is provided.

The boss of the second pulley 72 is rotatably supported by the second rotation shaft 59, and the casing 74 of the second wrist link 42 is fixed to the boss of the second pulley 72. The distal end side connecting member 43 is rotatably supported about the third wrist axis L3 at the distal end of the casing 74 of the second wrist link 42.

In the casing 74, the third pulley 71 is fixed to the second rotation shaft 59. In addition, the fourth pulley 75 is fixed to the front end side connecting body 43 in the casing 74. An endless transmission belt 76 is wound around the third pulley 71 and the fourth pulley 75. In the casing 74, a tension roller 83 for adjusting the tension of the transmission belt 76 is provided.

In the wrist 4A having the above configuration, when the driving pulley 55A is rotationally driven by the output of the motor 45, the rotational power is transmitted to the input pulley 56, and the input pulley 56 and the casing 58 are rotated. The first wrist link 41 including a rotation about the first wrist axis (L1). When the first wrist link 41 rotates about the first wrist axis L1, the second rotation axis 59 revolves around the first wrist axis L1. The rotation of the second rotation shaft 59 rotates the transmission belt 73, and the second wrist link 42 including the second pulley 72 and the casing 74 is centered on the second wrist axis L2. Rotate Furthermore, when the second wrist link 42 rotates about the second wrist axis L2, the front end side connector 43 revolves around the second wrist axis L2. The revolving belt 76 rotates by the revolving of the distal end body 43, and the distal end side body 43 including the fourth pulley 75 rotates about the third wrist axis L3.

In the wrist 4A having the above-described configuration, the first link length that is the distance between the first wrist axis L1 and the second wrist axis L2 of the wrist 4, the second wrist axis L2, and the first wrist axis L2 are formed. The second link length, which is the distance from the three wrist axes L3, is substantially the same. Furthermore, the pulley ratio, which is the ratio of the diameter of the first pulley 53 and the diameter of the second pulley 72, is 2: 1, and the diameter of the diameter of the third pulley 71 and the diameter of the fourth pulley 75 is increased. The ratio pulley ratio is 1: 2. Accordingly, the third wrist axis L3 moves on a straight line in the Z direction passing through the first wrist axis L1, that is, in the folded state, the first wrist link 41 moves to the first wrist axis ( When rotating α ° about L1), the second wrist link 42 rotates about -2α ° about the second wrist axis L2, and the distal end link 43 is connected to the third wrist axis L3. Rotate α ° around

1: dual arm robot 2: base
3: robot arm 4, 4A: wrist
5: end effector 6: controller
21: Key axis 31: first link
32: second link 33: wrist connection
40: proximal end connector 41: first wrist link
42: second wrist link 43: distal end connector
44: wrist drive device 45: motor
46: linkage 48: motor
49: bracket 50: flexible hose
51, 58, 74: casing 52, 59: axis of rotation
53, 55A, 71, 72, 75: pulley 57, 73, 76: transmission belt
61, 62: rotary drive 81-83: tension roller
55, 89 to 96: gear A1: first axis
A2: second axis L1: first wrist axis
L2: second wrist axis L3: third wrist axis
L4: fourth wrist axis

Claims (6)

A wrist that connects an end effector with a robot arm whose tip is moved within a predetermined plane,
A proximal side connection body connected to the robot arm,
A first wrist link connected with the proximal end connector so as to be rotatable about a first wrist axis defined in the proximal end connector;
A second wrist link connected to the first wrist link to be rotatable about a second wrist axis defined in the first wrist link;
A front end side connector connected to the second wrist link and rotatably around the third wrist axis defined in the second wrist link and connected to the end effector;
And a wrist drive device including a drive source for applying rotational power to the first wrist link, and an interlock device for interlocking the second wrist link and the tip side connection body to the rotation of the first wrist link.
An axis extending direction of each of the first wrist axis, the second wrist axis, and the third wrist axis is parallel to the predetermined plane,
The distance from the first wrist axis to the second wrist axis is equal to the distance from the second wrist axis to the third wrist axis,
The second wrist link rotates the second wrist link to the second wrist link when the first wrist link is rotated by an α ° about the first wrist axis from the state where the first wrist axis and the third wrist axis overlap. A wrist of the robot arm, wherein the robot arm is rotated by -2 [deg.] About the wrist axis and the α-connected end body is rotated by [[alpha] [deg.] Around the third wrist axis.
A pair of robotic arms whose distal end moves within a predetermined plane,
An end effector installed on each of the robot arms,
The wrist according to claim 1 for connecting the robot arm and the end effector;
And a controller for controlling the operation of the robot arm, the end effector, and the wrist.
The method of claim 2,
And the controller operates the wrist such that the first wrist shaft of both wrists is positioned between the second wrist shafts of both wrists.
The method of claim 2,
And the controller operates the wrist such that the second wrist axis of both wrists is positioned between the first wrist axis of both wrists.
The method of claim 2,
And the controller operates the wrist such that a straight line connecting the first wrist axis and the second wrist axis of both wrists is parallel to each other.
The method according to any one of claims 2 to 5,
The robot arm has a first link and a second link having a proximal end connected to one of the upper and lower sides of the first link at the distal end of the first link,
The drive source is installed in the proximal end connection body of the wrist, and the drive source is located on the one side up and down than the second link.

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